IOL's are commonly used to replace the natural lens of the human eye when the natural lens becomes sufficiently ineffective in focusing light on the retina. To accomplish this, the natural lens is removed through an incision in the eye, and the intraocular lens is inserted into the eye through the incision. This is all accomplished using known surgical techniques.
An IOL typically includes an optic and one or more fixation members for fixing the optic in the eye along the optical axis of the eye. The optic may be either hard and nondeformable or soft and deformable. The deformable optic is foldable about a fold axis and can be inserted through the incision into the eye in the folded condition. This has the advantage of requiring a shorter incision as compared with the length of the incision required for the insertion of an IOL having a hard or nondeformable optic. Once inserted, the deformable optic has sufficient resilience to return to its unfolded or undeformed state.
IOL's have small dimensions, e.g. the optic may be about 6 mm in diameter, and therefore are not easy to accurately fold. Many folding devices are known for folding of deformable optics.
It has been found that different surgeons prefer to fold the deformable optic about different fold axes. For example, in the case of an IOL having diametrically opposed fixation members extending from the deformable optic at about the 1:30 o'clock and 7:30 o'clock . positions, some surgeons prefer to fold the optic along a fold axis extending from about 3 o'clock to about 9 o'clock. Other surgeons prefer a fold having a fold axis extending from about 6 o'clock to about 12 o'clock. Still other surgeons may prefer a fold axis having another angular orientation relative to the fixation members.
The folding devices of which we are aware do not permit the surgeon to fold the optic about any one of a plurality of fold axes without removing the IOL from the folding device, reorienting the IOL and replacing the IOL into the folding device. Handling of the IOL increases the risk of damage to the IOL and loss of sterility. Although a forceps can accomplish folding of the IOL about a selected fold axis, the IOL must first be loaded into the forceps in the correct orientation, and this is difficult to accomplish primarily because of the small dimensions of the IOL and the resilience of the IOL.